Create proxy server for CORS issues (http-proxy package)

anticors-proxy-server.js

// Import required modules
const http = require("http");
const httpProxy = require("http-proxy");

// API target and proxy port configuration
const API_TARGET = 'https://pokeapi.co/api/v2/';
const PROXY_PORT = 8080;

// Create a proxy server
const proxy = httpProxy.createProxyServer({});

// Function to send error response
const sendError = (res, err) => {
    console.error('Proxy error:', err); // Log the error for debugging
    res.status(500).send({
        error: err.toString(),
        message: "An error occurred in the proxy"
    });
};

// Proxy error handling
proxy.on("error", (err, req, res) => {
    sendError(res, err);
});

// Function to enable CORS
const enableCors = (req, res) => {
    if (req.headers['access-control-request-method']) {
        res.setHeader('access-control-allow-methods', req.headers['access-control-request-method']);
    }

    if (req.headers['access-control-request-headers']) {
        res.setHeader('access-control-allow-headers', req.headers['access-control-request-headers']);
    }

    if (req.headers.origin) {
        res.setHeader('access-control-allow-origin', req.headers.origin);
        res.setHeader('access-control-allow-credentials', 'true');
    }
};

// Set header for CORS in proxy response
proxy.on("proxyRes", (proxyRes, req, res) => {
    enableCors(req, res);
});

// Create HTTP server and define request handling logic
const server = http.createServer((req, res) => {
    // Handle OPTIONS method for CORS preflight
    if (req.method === 'OPTIONS') {
        enableCors(req, res);
        res.writeHead(200);
        res.end();
        return;
    }

    // Proxy the request to the API
    proxy.web(req, res, {
        target: API_TARGET,
        secure: true,
        changeOrigin: true
    }, (err) => {
        sendError(res, err);
    });
});

// Start the server
server.listen(PROXY_PORT, () => {
    console.log(`Proxy server listening on port ${PROXY_PORT}`);
});